P53Δ37蛋白3′-5′核酸外切酶活性的初步研究

P53Δ37 Protein Exhibits 3′ 5′ Exonuclease Activity

1996年 Mum menbrauer等发现野生型 P5 3蛋白具有内在的依赖 Mg2 + 的 3′- 5′核酸外切酶活性。本研究对一种缺陷型 P5 3蛋白 P5 3Δ 37是否具有这种核酸外切酶活性进行初步研究。结果发现 :P5 3Δ 37蛋白同样具有 3′- 5′核酸外切酶活性 ,并随着蛋白量的增加而增加 ,但一磷酸鸟嘌呤对该外切酶活性没有抑制作用。哺乳动物细胞内有许多过程涉及到核酸外切酶功能 ,如 DNA复制、DNA重组及 DNA修复 ,因此 ,这一功能在 DNA复制。

Mummenbrauer et al. (1996) found that P53 protein exhibits 3′ 5′ exonuclease activity. This exonuclease activity is intrinsic to wildtype P53 protein, dependent on Mg 2+ , and it can be inhibited by addition of 5mmol/L nucleoside monophosphates. In the present study, we intended to know whether mutated P53 protein—P53Δ37 has this 3′ 5′exonuclease activity or not. The results reveal that P53Δ37 also has 3′ 5′exonuclease activity. It has more protein and more exonuclease activity, but this activity can not be inhibited by guanine monophosphate. There are many processes related to exonuclease activity in mammalian cells; for example, DNA replication, DNA recombination and DNA repair. The exonuclease activity of P53Δ37 protein may be important in these processes.